Abstract: A new anti-corrosion method for bolt has been developed, i. e composite coatings of sherardizing and dacromet. Through studying the anti-corrosion mechanism, coating structure of dacromet and sherardizing and comparing the salt-frog test and outdoor exposure test of dacromet and sherardizing coating, it was found that the salt-fog resistance of dacromet layer was good, the hardness of sherardizing layer was high, the performance of outdoor exposure test of composite coating was prior to dacromet. The application of composite coatings of sherardizing and dacromet on anchor bolts of bridge bearings could significantly improve their service life.

Key words: dacromet, sherardizing salt-fog test hardness, composite coatings

摘要： 介绍了一种新的螺栓防腐处理方法，渗锌 -达克罗复合涂层。通过研究达克罗和渗锌的防腐原理和涂层结构，比较达克罗和渗锌螺栓的中性盐雾试验和室外自然暴露试验，发现达克罗层耐中性盐雾性能好，渗锌层硬度高，室外自然暴露实验结果优于达克罗层，将达克罗和渗锌相结合的复合涂层的处理方式能大大提高桥梁支座锚固螺栓的使用寿命。

关键词: 达克罗, 渗锌, 盐雾试验, 硬度, 复合涂层